A theory, Conciousness + Unconsciousness:
When you're lucid your conscious mind does work, but you don't have a direct access to subconscious. It's just like being awake. On another hand, you can see your subconscious in methaphorical forms or hear it speak through DCs. It's still subconscious and unknown to us, otherwise we could decipher everything that happens it dreams and could predict anything there.

A different theory, Unconciousness + Unconsciousness:
When you're lucid the only difference from being unconcious is memory: you remember the memory that you're lucid and gain access to a small part of waking memory... but in all other respects you're unconscious. In this case you can't have an access to yourself (unconsciousness to unconsciousness), it would be like trying to jump over your own head.

Which of these two sounds more like truth?